One Man's Bug, Another's Feature

My laptop gives me two possibilities of controlling sound. I can play it on laptop speakers and I can play it on headphones (with laptop speakers going mute as soon as I plug it in). I think that these are standard modes available on any laptop.

However, there was sound in my headphones even when I pressed mute button. I considered this a great feature! In normal muting scenario, laptop speakers would play as soon as I unplug headphones. In this scenario, I could have speakers muted and headphones working. I do lot of work during night and this feature ensured that, even if I unplug headphones by accident, no sound will be heard.

What I considered feature, someone considered a bug. I noticed new driver on Windows Update for my audio card and as soon as I installed it, my favorite feature was gone. Someone decided that this inconsistent behavior needs to be fixed.

Headphones are now also muted when mute button is pressed. I can use headphones in “standard” way of auto-muting laptop speakers when headphones are inserted, but that also means that, in case of unplugging, I have laptop speakers playing at full volume.

I could roll back to previous version of driver and this would work for a while. However, I will need to reinstall laptop sooner or later and at that point in time I will get newest drivers over Windows Update. And that will be sad day for me.

Ice Is Not Liquid

I have read post on TSA blog that left me puzzled.

It lead me to conclusion that bringing ice through airport is allowed: “Ice is a solid. Therefore, ice is permitted through the checkpoint…”. Yes, this is from same organization that forbids you to take bottle of water through gate.

While I think that whole fluid restriction policy is stupid, this brings it to totally new level.

P.S. Additionally, they say that empty bottles can go through. Of course (from my own experience), you cannot bring 1 liter bottle with gulp of water through (since it is not empty). Probably reason is that this gulp makes whole bottle volatile…

Failed To Create Mapping

I tested Team Foundation Server 2010 a lot. Testing included creating project collections, adding solutions, removing everything, restoring from backup and doing this all over again.

Out of blue, I started getting “Failed To Create Mapping” error. Worst thing was that those messages referenced project collection that I already deleted.

I restored project from state before even adding it to source control and result was stubborn “Failed To Create Mapping”.

However, there is solution. There is configuration file at

%LOCALAPPDATA%\Microsoft\Team Foundation\3.0\Cache\VersionControl.config

Every Team Foundation Server connection gets stored there. Once I deleted ServerInfo for non-existing connection, everything was good again.

Hyper-V and Windows Server 2000

I haven’t had this one in a while.

Once you install all updates available on Windows Update on your Windows Server 2000 under Hyper-V, this is what happens.

What have I done:

• install Small Business Server 2000
• start SBS setup to create domain and install SQL server component
• install SQL Server 2000 Service pack 4
• install SBS 2000 Service pack 1a
• install Hyper-V Integration components
• go to Windows Update and install all recommended updates (Express)
• go to Windows Update and install all recommended updates (Express)
• …

Crash happens after batch of 88 updates.

Setting SPF Records With Google Apps

SPF records are great thing. In theory they should help fight spam and prevent forgery of your e-mail address. However, it may cause troubles if you do not configure it properly.

Did you ever saw this:

This is an automatically generated Delivery Status Notification

Delivery to the following recipient failed permanently:

    example@example.com

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 553 553 See http://spf.pobox.com/why.html?sender=jmedved%40jmedved.com&ip=209.85.218.215&receiver=he-dc2-l3.avalon.hr (#5.7.1) (state 14).

There are two reasons why this may go unnoticed.

First one is that not many domains implement these checks. If domain does not check your SPF records, it will not block your e-mails. Almost all your e-mails will pass without any trouble to most of your destinations. That “almost” part is problematic.

Further, even if domain blocks your e-mail, it may opt not to report error. This is worst of all since neither your recipient will receive message neither you will receive error. It is great when e-mail just doesn’t work.

If you use Google Apps, you need to modify your SPF records to include “aspmx.googlemail.com”. However, there are some unofficial reports that this does not work all the time. It seems that you need “_spf.google.com” in your SPF record also. Since DNS takes ages to propagate, I opted to include both of these at once. Better safe than sorry.

Additionally, every SPF record has “all” mechanism in order to decide what to do with e-mails that are not caught by any other mechanism. This is for most of hosts written as “-all” which causes fail for all hosts not in list. Google Apps requires this to be “~all”. This is so called soft-fail. Your final destination will not be affected by it - it will only happen during internal mail routing.

How final record should look like, it depends on your particular configuration. However, I will give you what I added in TXT record:

v=spf1 a mx include:aspmx.googlemail.com include:_spf.google.com ~all

Your requirements may very, but not by much.

P.S. If you do not have access to your DNS records or you just want to check whether your change has propagated through DNS system, it is helpful to use SPF Query Tool. It is online and hassle free.